Jesse submitted a height of 17'8" to Guinness World Records for his Giant Amaranth plant (Amaranthus Australis). He is awaiting confirmation from Guinness. The stem circumference on this plant is now over 52 inches around. Hopefully, I can catch up to his plant before the end of the year. I'm currently at 16 ft. My growing season is quite a bit longer in New Jersey, and these plant very late in the year; so there is a chance.